Biting winds, rain and snow to batter the country

Transport chaos is expected across the country this week as the worst winter weather of the year sweeps the country, bringing snow, icy gales and fog.

On Tuesday morning, the weather caused delays in Queenstown and Wellington airports. While the ice caused disruptions in Queenstown, it was a thick blanket of fog that kept flights grounded in Wellington. Both recommend checking their websites for flight changes.

Lloyd Burr/Newshub.

Bitterly cold southerlies are expected right across the country, with wind chill and heavy rain cause for concern, according to Metservice.

"High impact severe weather" is expected from Wednesday through to Friday, with Metservice warning of flooding, severe gales and heavy rain. The extreme weather may cause transport problems and stress to livestock.

The cold front will move up from the south from Tuesday, and is expected to deepen across the east of the North Island on Wednesday, continuing north on Thursday.

The front is expected to bring significant snow above 200m across many parts of the South Island, and Air New Zealand on Tuesday morning warned disruptions are possible.

The biting wind and snow could cause problems for livestock, and many higher roads are expected to be affected from Southland to Banks Peninsula on Tuesday.

Motorists have been warned to expect snow on the South Island alpine passes and up to 20cm could accumulate near the summit of Porters Pass between Tuesday and Thursday morning.

The Milford Road (State Highway 94) is forecast to be affected from 4am till 11am on Tuesday, with possibly up to 8cm of snow settling near the tunnel.

Snow showers could hit the summit of the Dunedin-to-Waitati Highway (SH1) at times from Tuesday afternoon to Thursday morning.

MetService has already warned New Zealanders to wrap up for a chilly week that is expected to include flooding and gales.